It has been shown that stress modifies the allocation of attentional resources such that the perceptual field is narrowed (Staal, 2004), and that attention modulates early visual mechanisms such as contrast sensitivity (Carrasco, Penpeci-Talgar, & Eckstein, 2000). Here, we investigated whether social stress has an impact on the sensitivity to different spatial frequencies. We used the method of limits to estimate the contrast sensitivity function (CSF) of nine participants after having submitted them to a socially stressful or a control condition. In the stress condition, participants underwent the Trier Social Stress Test for Groups (TSST-G; Von Dawans, Kirshchbaum & Heinrichs, 2011), a standardized laboratory stressor. The control condition was identical to the TSST-G condition save for the socioevaluative threat component. The CSF task consisted of 60 trials in which participants adjusted the contrast of a Gabor patch composed of one of 6 spatial frequencies (0.6, 1.2, 2.4, 4.8, 9.6, and 19.2 cpva) until they detected its presence. The number of trials was kept low to ensure that the stress manipulation was effective throughout the CSF measurement (salivary cortisol was measured 7 times during the experiment). To compensate, we resampled the 126 possible combinations of 5 participants, and performed a sign test to compare the contrast sensitivity (1/threshold) across the two experimental conditions. Our results show that social stress alters the CSF, reducing sensitivity to low-to-medium spatial frequencies (for 0.6 to 4.8 cpva, inclusively), and maximum contrast sensitivity (423.45 vs. 452.63). Moreover, our curve-fitted results indicate a shift of peak sensitivity toward higher spatial frequencies (6.63 vs. 4.8 cpva), and a slight narrowing of the FWHM (4.3 vs. 4.45 octaves), induced by stress, all pâ€™s<.001. Potential implications for higher-level visual tasks such as emotion recognition will be discussed.